The bacterial number was expressed as CFU g-1 dry weight of soils. Data are the average of three experiments and were analyzed using Student’s t-test (P ≤ 0.05). Letter ‘a’ indicates the highest value, and ‘g’ the lowest value. The same letters within a column mean no significant differences exist
between the numbers. Growth-promoting effects of Lu10-1 on mulberry seedlings All mulberry seedlings could survive in soils treated with Lu10-1. Seven days after the treatment, the growth of seedlings in the treated soil was not significantly different (P ≤ 0.05) from that in untreated soil. However, ZD1839 price 14 days and 21 days after the treatment, growth was significantly better (P ≤ 0.05) in the treated soils: the seedlings were taller and the fresh weight of roots and of whole seedlings was greater. No significant differences were found between the seedlings in sterile PR 171 and non-sterile soils (Table 1). The results indicate significant growth-promoting effect of strain Lu10-1 on mulberry seedlings. Table 1 Plant-growth-promoting effects of Lu10-1 on mulberry seedlings. Planting soil Days after inoculation Height (cm) Root
fresh weight (g/plant) Seedling fresh weight (g/plant) Inoculated Control Inoculated Control Inoculated Control Sterile soil 7 12.9a(a) 12.7a 0.032a 0.032a 0.104a 0.101a 14 25.4a 18.8b 0.106a 0.071b 0.254a 0.195b 21 31.5a 22.5b 0.121a 0.082b 0.311a 0.238b Non-sterile soil 7 13.1a 13.0a 0.040a 0.032a 0.110a 0.109b 14 24.4a 18.4b 0.107a 0.074b 0.244a
0.195b 21 31.2a 22.2b 0.120a 0.080b 0.308a 0.236b (a) The same letters within a column mean that no significant differences exist between the numbers; the values are the means of all the seedlings sampled. Quantification of endophytic population of Lum10-1 in mulberry seedlings To quantify the endophytic population, Lum10-1 was re-isolated from surface-disinfected roots, stems, and leaves of mulberry seedlings (Fig. 5). The results showed that the bacteria could be re-isolated from surface-sterilized roots and stems on P-type ATPase the 7th day after inoculation, implying that the bacteria could successfully establish their presence in roots and stems within 7 days. In the case of leaves, it took 14 days after inoculation, indicating that the bacteria had spread from roots to leaves. Even 49 days after inoculation, the bacteria could be recovered from all parts of the plants, and no damage to the plants was visible. The results of monitoring the growth inside the plants are as follows. The number of bacteria increased initially and fell later, ultimately https://www.selleckchem.com/products/OSI-906.html stabilizing at 1-5 × 105 CFU per gram of fresh plant tissue. The control seedlings did not yield bacterial colonies when their surface-disinfected roots, leaves, and stems were plated on rifampicin and streptomycin nutrient agar. The above results show that strain Lu10-1 is an endophyte and can spread systemically within mulberry seedling. Figure 5 Population of Lum10-1 in the roots, stems, and leaves of mulberry seedlings.